This invention relates to a system for fastening triangularly shaped surfaces, and preferably equilateral triangle shaped surfaces. The fastening system forms an integrated and pleasing design element on the triangularly shaped surface and is made up of a single, repeating overall design for all triangularly shaped surfaces.
The system allows for two triangularly shaped surfaces to be fastened in more than one orientation, specifically, one orientation in which the three apexes of one triangularly shaped surface align with the three apexes of another triangularly shaped surface, another orientation in which one apex of one triangularly shaped surface aligns with the midpoint of a side of the other triangularly shaped surface and the apex opposite that side of the other triangularly shaped surface aligns with the midpoint of the side of the first triangularly shaped surface opposite its aligned apex, and an orientation in which one apex of one triangularly shaped surface is fastened to an apex of another triangularly shaped surface and either or both of the remaining two apexes are either not fastened to any triangularly shaped surface or are fastened to one apex of yet another triangularly shaped surface.
Typically, fasteners require a pair of different, interlocking surfaces, one functioning, say, as a male and the other, say, as a female. For example, the common hook and loop fastening system (such as VELCRO.RTM.) requires one surface to have a hook element (male), and another to have a loop element (female). Two surfaces with hook elements can not be fastened together, nor can two surfaces with loop elements. Furthermore, hook and loop fastening systems lack elegance as an integrated design element.
In another prior art example, LEGGO.RTM. blocks are fastened together by receiving the bumps of one surface, the male surface, into the dents formed on the reverse surface, the female surface. While the bumps and dents do create a pleasing design, this system of bumps and dents is limited in that two bump surfaces cannot be fastened together, nor can two dent surfaces. Additionally, this fastening system can fasten pairs of blocks in only basic, limited orientations.
Further examples from the prior art can be seen in, for instance, Piersch, U.S. Pat. No. 5,222,902, describing a female fastening assembly and an interlocking male fastening assembly. The fastening assemblies of Piersch, `902 lack elegance as a design element and are not adaptable to allow multiple configurations of the pieces to be fastened. Olsson, U.S. Pat. No. 5,033,903, describes two elements to be fastened by having one element provided with a bump and the other element provided with a recess. Again, the separate pieces can not be interchanged. Other references describe improvements to fasteners with separate male and female members, such as Blakely, U.S. Pat. No. 3,901,538 (for quickly fastening a male and female fastener) and DeFrese U.S. Pat. No. 3,944,377 (for fastening a male and female member at a selected angle). Each of these prior fasteners have separate male and female fastening elements as well as other deficiencies.
What is desired is a fastening system in which opposing surfaces are composed of a single, pleasing, unisex design. What is further desired is a fastening system that allows for triangularly shaped surfaces to be joined in various interesting orientations, such as, at the least, three apex to three apex orientation, one apex to one midpoint orientation, and one apex to one apex orientation. What is further desired is a fastening system usefull for fastening the sides of tetrahedral solid blocks or other solid blocks in which some or all the sides are triangularly shaped, in various interesting orientations, such as, at the least, three apex to three apex orientation, one apex to one midpoint orientation, and one apex to one apex orientation.